Attitude and orbit control analysis of a solar sail spacecraft for Space sunshade missions in the vicinity of the sub-Lagrange 1 point

Sammanfattning: This Master thesis report contains a complete attitude and orbit control analysis for solar sail spacecraft in the Circular-Restricted-3-Body-Reference frame. The overall goal of the project is to drive one solar sail from the edge of the Earth Sphere of Influence to a vicinity of the sub-Lagrange1 point. First, a trajectory control optimization has been performed using a direct transcription method to find an optimal control to guide the solar sail to a neighborhood of the sub-Lagrange 1 point. Then, the stability of the artificial equilibrium points in the Sun-Earth system has beeninvestigated. Two options are detailed in the following study: Halo orbits which correspond to periodic motion, and the implementation of a PD-controller on the solar sail normal vector to make any artificial equilibrium point asymptotically stable. An attitude control analysis study has been performed to estimate the needed torques for all the mission phases. This report is one of the first step for Space sunshade missions in the vicinity of the sub-Lagrange 1 point.